Tire Conicity and Ply Steer Effects on Vehicle Performance

Conicity and ply steer are lateral forces developed by tires whose importance has surfaced with radial tire popularity. Understanding their significance is enhanced by knowing their dependence on measurement and usage parameters and tire construction features. Of the two tire forces, conicity and ply steer, conicity seems to be the most troublesome due to its relationship to vehicle pull as opposed to ply steer effects which go unnoticed in normal applications. Their effects on vehicle performance are manifested in vehicle pull and vehicle drift or dog tracking. Knowing their individual vehicle performance characteristics offers insight into handling related field-service problems more effectively.